Cob mortar

[vtrac at alternatives.com]

>Jud Malone wrote:
>
>>  I'm in the midst of building a stone foundation for a cob house.  Up
>> to this point I've been laying the stones dry(I haven't reached ground
>> level yet and my foundation trench is about 2 1/2 feet deep).  But I
>> was thinking that I would use mortar once I reach ground level in
>> order to keep drafts and critters out.  My first question is: how
>> useful is mortar for keeping out drafts and critters?  Could I just
>> plaster over the stone on the inside of the building once I'm done
>> with the same effect?  My other question is: has anybody used cob for
>> mortar, and how well does it work?  Thanks in advance. Jud Malone
>
>
>Jud,
>
>I'm totally excited for you!  I for one would appreciate an occasional
>report on your progress.  I still don't have the nerve to go do it
>myself--I just don't know where to do it.
>I was just thinking the other day that there hasn't been much activity
>on the list, and not only that but there really aren't too many people
>actually building--most of us are still dreaming and planning.  So three
>cheers for Jud!

Hi Jud,

I am currently working on 2 cob structures. One building is on the mid
coast of British Columbia where it is very windy, wet and cool in the
winter. Our foundation there is a dry stack but we have filled the cracks
with a very sandy cob mortar. This seems to be working pretty well and is
drying hard but how it will hold up to the moisture at the ground level is
yet to be seen. In some parts of the foundation that are very wide there
are few drafty openings and we haven't used any mortar. Where any cracks do
exist we will probably cob the interior walls right to the floor. Because
we are building a cafe, there are cob benches around many of the walls
effectively solving any draft problems.  The other structure is a small
meditation space here in Vancouver. Because the foundation wall is on the
narrow side (14 inches) I resorted to using a cement mortar for strength
filling in any cracks.  So go for it.  My sense is that the cob mortar will
work just fine but better to ask someone who has been living in a cob home.
Good luck.

Ian Marcuse
Down to Earth Building Bee